Engineering

I am in need of a non-contact liquid level sensor for small drums. I found that Madison Co. has created a ultrasonic sensor with a range of 4” to 70”, it be used on 30 and 55 gallon drums and requires no software installation or programming. I was wondering if anyone knows of any other companies that make such a sensor so I could compare them and see if they are worth buying or if I should make my own?

First off we have all heard of the tether into space. How much heat could a pressurized helium filled carbon nanotube chamber take before bursting and would it be possible to make such a device? I want heated gas tube inside and helium filled sectional valved outer wall in order to sustain the weight of the tether. The heated gas inside would be non explosive. I do not know anyplace else to discuss this or I would have tried there first.

What is the Thrust to Weight ratio? im planning to build a scale model of a floating island. im going to make it out of toothpicks(building materials), a mini thermonuclear reactor(energy) and fans(propulsion). for the purpose of having a floating, controllable runway with the ability to land other model planes on it. i wana see if it is even possible to make such a thing.

i want to learn about mechanics such as the movements of a bionic arm, but since it is a decently new topic in science, i wouldn't think i might find much. So if you can recommend a good reliable book that just introduces mechanics to its reader would be fine..

Hello, I am looking for some freeware that would allow me to take a scanned topography map and run a hydrolgy analysis. I would like to simulate a rainfall to see where the runoff accumulates. I have no budget for this which is why I am asking for freeware advice. I know the answer might be a complicated process involving several small programs. Any help would be appreciated. Thank you

In digital-to-analog converters, what is charge redistribution? Does it have something to do with switched capacitors?

I'm desperately trying to verify a FEM analysis done on a system of two permanent magnets. I'm trying to analytically find the force between two large neodymium magnets spaced 1/8 inch apart. This problem would be easier if the magnets were oriented such that their magnetized planes were parallel with each other, but this analysis requires that the magnets be PERPENDICULAR to each other. Since the magnets are close to each other, considering the dimensions of the magnets themselves, I cannot make the magnets into dipoles. The question is, then: HOW DO I ANALYTICALLY (NO FEA OR ONLINE CALCULATORS) determine the force (normal and transverse) between these two perpendicu…

In the wikipedia article on solar thermal rockets they write that: "Direct solar heating involves exposing the propellant directly to solar radiation. The rotating bed concept is one of the preferred concepts for direct solar radiation absorption; it offers higher specific impulse than other direct heating designs by using a retained seed (tantalum carbide or hafnium carbide) approach. The propellant flows through the porous walls of a rotating cylinder, picking up heat from the seeds, which are retained on the walls by the rotation. The carbides are stable at high temperatures and have excellent heat transfer properties." What is a retained seed? Is it a crystal?

What future technology will allow us to make computer chips smaller than 1 nm?

we are experiencing what appears to be a slow air leak in the following setup: low pressure sensor connected to a tygon tube via 1/8" hose barb; the tygon tube is submerged in a liquid; the hydrostatic pressure of the liquid compresses the air in the tube; the sensor measures the air pressure; the linear relationship between hydrostatic pressure and liquid level enables liquid level determination problem: over the course of several weeks we've noticed a slow, steady drop in pressure while a constant liquid level is maintained. of note, the small "slug" of water at the bottom of the tube climbs slowly and steadily indicating an air leak. two questions: 1 - if…

Hi all, this will be my first post. I have decided to attempt to build my own wind turbine using canablised parts for as cheap as possible. Iknow I can get the wind to drive a permenant magnet motor. But which one? I need a high voltage (30v ish), high current, low rpm (400 ish) motor that I can canablise Any ideas? Thanks in advance Tranq

I didn't know where to put it but I think it belongs best to electronics. In How a Projector works? they write that the composite video and S-video signals are routed to a Video Decoder circuit. Most digital projectors include a video decoder and a light engine. The video decoder converts video data received by the projector into pixel and color data. My question is: How exactly does the video decoder do this conversion?

I've been doing some digital electronics in my studies lately, and I'm just not getting this part. Well, rather, I can do all the work just fine, I'm just not understanding something that my lecturer claims is unimportant. I'm sure many of you know what it is, but to make the problem I have clear I'm going to explain: S NAND (NOT)Q = A = Q R NAND Q = B = (NOT)Q They both seem simple enough, but I'm not getting how it /starts/. On start-up, S and R are defined, but I can't fathom how S[or R] NAND (NULL) gives a value at all. My best guess would be to set S and R = logic 0 to start with, so that regardless of (NULL) the NAND would be logic 1, but A and B can't…

Can anyone help me with this problem? I have a large glass bottle washer in the factory in which I work. The bottles are transported around the machine (upside down) in round metal carriers. As the bottles travel thorugh the machine they are subjected to a variety of treatments to enusre they are clean. After the treatments are complete the bottles enter a spray rinse section which uses a blend of hard and softwater to achive a hardness of around 120ppm. Once the bottles are finished in the rinse section the bottle carriers are turned 180 degrees and we rely upon gravity for the bottles to fall out. If we drift away from this hard/soft water mix of 120ppm the bottl…

Long ago, I read in a science-fiction novel about a guy that went skydiving from orbit. He had on a spacesuit with ablative plating and everything. My question is: with today's technolgy, is it possible to do that? Assuming we had a really well-built spacesuit with ablative plating and some means of deorbiting, can it be done? Assuming it can be done, can we drop the prospective thrill-seeker at a given point on the planet, and if so, how much accuracy can we expect? I'm not picturing landing from orbit onto a moving vehicle, but perhaps getting within a few miles or so of one's destination sounds nice. On a related note, what's the smallest orbital vehicle we have th…

So there are several ways we could get off this rock, and also several ways to travel somewhere once we do. Which practical method is your favorite? I think for liftoff I would prefer a launch loop for the absurd cheap launch capacity from ground-based electricity. Alternately, a nuclear lightbulb, for its high specific impulse and flexibility. Or Project Orion (no relation to the shuttle of the same name) for the awesomeness factor of being able to lift an entire city, if people didn't mind nuking the atmosphere while sitting on a pile of nukes, and also the only craft I am aware of that could both lift off and travel to another star. For traveling after lift-off…

which would use up less energy, going up the stairs one at a time or two at a time?

Hello! Here is a topic that maybe hot on our tails in about 50 years, AI. Okay first for AI to come to life we need full knowlege of the human brain, this includes emotions, thought, institinct and so on. 2nd we need enough computing power to code the complexity of the human brain (we would start small e.g mouse) in a "robot". Now i will discuss how the second aspect could be plausable in 50 year. We are now developing quantum computers, these computers are at their developing stage. About a few years ago 7 atoms figures at 5x3=15. Now that might not seem much but we are only talking about 7 atoms seen as there are millions of atoms in a mm we are talking abo…

If it is possible to do this As intecatly as this http://www.youtube.com/watch?v=t2sCCN3tpp0 There are even multiple open source designs for such machines. And we can use metal powder as well as plastic powder and filler powder (which we can). Then what is the problem with giving such a machine it's own design and letting it make a copy of itself? It might need a folding part or to be built in two parts as to obay the laws of size. Such a machine is reliant on energy but should be able to make it's own supply structure. The only things it would need from outside would be plastic, filler and metal powder and an electricity supply or materals to har…

Well I must say the technology we have now there is not much we can do.The TV shows that shows how to destry a asteroid the technology we have will not do that.

Suppose, there's a shorted coil which has a wire resistance R. Also, current i is flowing through the wire. Then, my book is saying that flux linkage "lamda" satisfies the equation " - i R = d(lamda)/dt "

Hello all, I was looking at a corn field not long ago and thinking about the optimal shape of the field's surface to maximize yield. Why do we keeps fields flat ? If instead one were to shape them with hills and valleys, say as a sine wave, the net surface area would be much more than the surface of a flat landscape - that would make for more space to grow cucumbers, salad, carrots ... Of course the wavelength of the sine wave should be greater than the average size of the plants grown, so the vegetable themselves wouldn't "fill the holes". Although, the hills shouldn't be too steep so they wouldn't cast too big a shadow. What do yo think ? McCrunchy

Im looking for a material that can achieve a moldable, low viscosity liquid phase and then solidify into the shape i want. It has to be transparent, able to absorb... or hold... water, highly gas permeable, and biologically inert. We've experimented with Nafion, various RTV Silicone rubbers, and agarose. Anyone have anything else that might come to mind? Just looking to broaden horizons here

BIT01 wrote:As all of you know I am trying to build a hovercraft. My problem is that I need to know how much air I can pump into it to run correctly. Any formulas and assistance will be great. Thanks.

The TV shows star treck and star wars that show those big space ships or SSTO make me laugh. No propulsion system today allows SSTO like those scfi shows. May be in 20 years from now we may get a very very very small crude SSTO but will be nothing like the scfi shows.The big problem is propulsion and that is why we must use stages not a SSTO .There has been some work on very small crude SSTO but even than the propulsion does not allow it. Why will the scfi shows not get it right?